diff --git a/BloubWorld/genbloubs.f90 b/BloubWorld/genbloubs.f90
index d0e7d88..1f32d8a 100644
--- a/BloubWorld/genbloubs.f90
+++ b/BloubWorld/genbloubs.f90
@@ -7,8 +7,7 @@ program genbloubs
   character(200)        :: filename
   character(30)         :: str
   type(t_bloubs)        :: bloub
-
-  integer, parameter    :: idu = 33
+  integer               :: idu
 
   i = IARGC()
   if (i .ne. 2) then
@@ -24,14 +23,15 @@ program genbloubs
 
   ! print *, "generating ", nbbloubs, "bloubs to ", filename
 
-  open(unit=idu, file=trim(filename), form='unformatted',     &
+  open(newunit=idu, file=trim(filename), form='unformatted',     &
                  action='write', status='replace')
 
   do i = 1, nbbloubs
+
     bloub%nick = 'noname  '
     bloub%alive = .TRUE.
     call random_pv(bloub)
-    bloub%radius = 0.028
+    bloub%radius = 0.030
     bloub%seq    = 0
 
     write(idu) bloub              ! no error control ?